You can check whether your shipment has undergone an ETD or ETA change from your shipment's detail screen.
To do so, click on ‘View alerts list’ on the left upper corner, just above the first timeline milestone.
To go back to the list of milestones, click on ‘View timeline’.
In addition to that, you can also check your shipments with an ETA change by going to the 'Dashboard' page and selecting ‘Last ETA change’ in ‘My shipments’ section: